Langerhans cell histiocytosis is a rare disease in children. However, Langerhans cell histiocytosis encompasses a wide spectrum of clinical presentations and mimics other conditions. A 1-year-old boy presented with signs of periorbital cellulitis that initially responded to antibiotics, but remained as a same-sized mass with serial orbital computed tomography. The lesion was partially excised. Histopathology and immunohistochemical staining confirmed the diagnosis of Langerhans cell histiocytosis. This case demonstrates that in patients with periorbital cellulitis which has relapsed or responded inadequately to antibiotics, further investigation should initiated to rule out other inflammatory causes.